Tui De Roy / Marine iguana (Amblyrhynchus cristatus) basking on driftwood, Fernandina Island, Galapagos, South America.

Tui De Roy / Darwin's small ground finch (Geospiza fuliginosa), inspecting Galapagos giant tortoise for ticks, Isabela Island, Galapagos, South America.

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) yearling pup playing with own air bubbles in shallows, Gardner Islet, Espanola Island, Galapagos, Ecuador

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) pups playing at sunrise, Puerto Egas, Santiago Island, Galapagos, Ecuador

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) female and male on red volcanic beach, Rabida Island, Galapagos, Ecuador

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) female resting in shallows, Bainbridge Islets, Galapagos, Ecuador

Tui De Roy / Galapagos sea lion (Zalophus wollebaeki) pups playing in shallows, Sombrero Chino, Santiago Island, Galapagos, Ecuador

Tui De Roy / Galapagos hawk (Buteo galapagoensis) landing on mating pair of Galapagos giant tortoise (Chelonoidis vandenburgh) Alcedo Volcano, Isabela Island, Galapagos.

Tui De Roy / Epanola saddelback tortoise (Chelonoidis hoodensis), with Galapagos mockingbird (Mimus parvulus) perched on carapace, Espnola Island, Galapagos.

Tui De Roy / Alcedo giant tortoise (Chelonoidis vandenburghi), Alcedo Volcano, Isabela Island, Galapagos

Tui De Roy / Galapagos sea lions (Zalophus wollebaeki) sub adult males playing with starfish, Mosquera Islet, Galapagos.

Tui De Roy / Alcedo giant tortoise (Chelonoidis vandenburghi), Alcedo Volcano, Isabela Island. This is where the largest extant population exists, acting as ecosystem engineers by maintaining open meadows and digg...

Tui De Roy / Wolf giant tortoise (Chelonoidis becki) two males fight briefly over mating rights. Wolf Volcano, Isabela Island, Galapagos

Tui De Roy / Wolf giant tortoise (Chelonoidis becki) in habitat. Hybrids of mixed parentage with different shell shapes are scattered far and wide on the rugged west slope of Wolf Volcano. Wolf Volcano, Isabela Is...

Shane Gross / Panamic Cushion Sea Star (Pentaceraster cumingi) and a school of Yellow-tailed Grunt (Anisotremus interruptus), Galapagos Island, Ecuador. December.

Shane Gross / Galapagos Sea Lion (Zalophus californianus wollebacki) resting on rocks at sunset on North Seymour Island, Galapagos, Ecuador. December.

Shane Gross / Galapagos sea lion (Zalophus wollebaeki) plays in the surf, San Cristobal Island, Galapagos, Ecuador. December.

Shane Gross / Galapagos green sea turtles (Chelonia mydas agassizii) feeding on seaweed growing on lava rocks off Isabela Island, Galapagos, Ecuador. December.

Shane Gross / Galapagos sea lion (Zalophus wollebaeki) hunting shoal of Black striped salemas (Xenocys jessiae), Rabida Island, Galapagos, Ecuador. December.

Andres M. Dominguez / Dead Lang's short-tailed blue butterfly (Leptotes pirithous) in a river with bacterial film, Los Alcornocales Natural Park, Southern Spain, September.

Andres M. Dominguez / Dead Lang's short-tailed blue butterfly (Leptotes pirithous) in a river with bacterial film, Los Alcornocales Natural Park, Southern Spain, September.

Lucas Bustamante / Sierra Negra giant tortoise (Chelonoidis guntheri) Isabela Island, Galapagos Islands.

Lucas Bustamante / Marine Iguanas (Amblyrhynchus cristatus) basking. Fernandina Island, Galapagos Islands.

John Shaw / Yellow warbler (Setophaga petechia aureola) on lava rocks. Isabela Island, Galapagos. May.

John Shaw / Great frigatebird (Fregata minor) male at nest site, with gular sac inflated to attract females. Genovesa Island, Galapagos, May.

John Shaw / Sally lightfoot crabs (Grapsus grapsus) on the beach at Puerto Egas, Santiago Island, Galapagos, May.

Nick Hawkins / Galapagos sea lion (Zalophus wollebaeki), three resting underneath school bus. Isabela Island, Galapagos. 2017.

Nick Hawkins / Marine iguana (Amblyrhynchus cristatus) basking on volcanic rock at coast. Isabela Island, Galapagos.

Nick Hawkins / Galapagos green turtle (Chelonia mydas agassizi) swimming above sea floor with shoal of fish in background. Off San Cristobal Island, Galapagos.

Nick Hawkins / Sergeant major (Abudefduf sp) schooling in mangroves of Isabela Island, Galapagos.

Tui De Roy / Red-footed booby (Sula sula), pair nest building in tree. Darwin Bay, Genovesa Island, Galapagos.

Tui De Roy / Nazca booby (Sula granti) in flight at dusk. Punta Suarez, Espanola Island, Galapagos.

Tui De Roy / Flightless cormorant (Phalacrocorax harrisi), two on rock. Bird drying wings in foreground with other sitting on nest in background. Cape Douglas, Fernandina Island, Galapagos.

Tui De Roy / Flightless cormorant (Phalacrocorax harrisi), Punta Espinosa, Fernandina Island, Galapagos

Tui De Roy / Blue-footed booby (Sula nebouxii), group of eight diving into sea to fish. Punta Gavilanes, Fernandina Island, Galapagos.

Tui De Roy / Blue-footed booby (Sula nebouxii), group fishing underwater. Itabaca Channel, Santa Cruz Island, Galapagos.

Tui De Roy / Blue-footed booby (Sula nebouxii) diving towards sea, folding wings. Northeast coast, Santiago Island, Galapagos. Sequence 1/2.

Tui De Roy / Blue-footed booby (Sula nebouxii) landing. Punta Vicente Roca, Isabela Island, Galapagos.

Tui De Roy / Blue-footed booby (Sula nebouxii) coming in to land. Punta Vicente Roca, Isabela Island, Galapagos.

Tui De Roy / Blue-footed booby (Sula nebouxii) perched on rock at coast. Santa Fe Island, Galapagos. August 2015.

Tui De Roy / Blue-footed booby (Sula nebouxii), pair in courtship display. Punta Pitt, San Cristobal Island, Galapagos. April 2017.

Tui De Roy / Blue-footed booby (Sula nebouxii), five diving into sea. Espumilla Beach, Santiago Island, Galapagos.

Tui De Roy / Alcedo giant tortoises (Chelonoidis vandenburghi) group resting in water on moonlit night to keep cool, Alcedo Volcano, Isabela Island, Galapagos

Tui De Roy / Alcedo giant tortoise (Chelonoidis vandenburghi) walking, Alcedo Volcano, Isabela Island, Galapagos

Tui De Roy / Alcedo giant tortoise (Chelonoidis vandenburghi) pair mating in shallow pool, with two others resting nearby. Alcedo Volcano, Isabela Island, Galapagos

Tui De Roy / Western Santa Cruz giant tortoises (Chelonoidis porteri) resting in water, South coast (Las Palmitas), Santa Cruz Island, Galapagos

Tui De Roy / Western Santa Cruz giant tortoise (Chelonoidis porteri) feeding on grass, El Chato II, Highlands, Santa Cruz Island, Galapagos

Tui De Roy / Western Santa Cruz giant tortoise (Chelonoidis porteri) portrait, Highlands, Santa Cruz Island, Galapagos